<template>
    <!-- 商品分类导航 -->
    <div class="type-nav">
        <div class="container" >
            <div  @mouseenter="itemWrapEnter" @mouseleave="itemWrapLeave">
                <h2 class="all">全部商品分类</h2>
                <transition name="sort">
                    <div class="sort" v-show="showSort">
                        <div class="all-sort-list2" @click="toSearch">
                            <!--一级分类-->
                            <div class="item"
                                 :class="{itemHover:currentIndex===index}"
                                 @mouseenter="itemEnter(index)"
                                 v-for="(c1,index) in categoryList" :key="c1.categoryId">
                                <h3>
                                    <a href="javascript:" :data-categoryName="c1.categoryName" :data-category1Id="c1.categoryId">{{c1.categoryName}}</a>
                                    <!--<router-link :to="`/Search?categoryName=${c1.categoryName}&category1Id=${c1.categoryId}`">{{c1.categoryName}}</router-link>-->
                                    <!--<a href="javascript:;" @click="toSearch({categoryName:c1.categoryName,category1Id:c1.categoryId})">{{c1.categoryName}}</a>-->
                                </h3>
                                <div class="item-list clearfix">
                                    <div class="subitem">
                                        <!--二级分类-->
                                        <dl class="fore" v-for="c2 in c1.categoryChild" :key="c2.categoryId">
                                            <dt>
                                                <a href="javascript:" :data-categoryName="c2.categoryName" :data-category2Id="c2.categoryId">{{c2.categoryName}}</a>
                                                <!--<router-link :to="`/Search?categoryName=${c2.categoryName}&category2Id=${c2.categoryId}`">{{c2.categoryName}}</router-link>-->
                                                <!--<a href="javascript:;" @click="toSearch({categoryName:c2.categoryName,category2Id:c2.categoryId})">{{c2.categoryName}}</a>-->
                                            </dt>
                                            <dd>
                                                <!--三级分类-->
                                                <em v-for="c3 in c2.categoryChild" :key="c3.categoryId">
                                                    <a href="javascript:" :data-categoryName="c3.categoryName" :data-category3Id="c3.categoryId">{{c3.categoryName}}</a>
                                                    <!--<router-link :to="`/Search?categoryName=${c3.categoryName}&category3Id=${c3.categoryId}`">{{c3.categoryName}}</router-link>-->
                                                    <!--<a href="javascript:;" @click="toSearch({categoryName:c3.categoryName,category3Id:c3.categoryId})">{{c3.categoryName}}</a>-->
                                                </em>
                                            </dd>
                                        </dl>
                                    </div>
                                </div>
                            </div>
                        </div>
                    </div>
                </transition>
            </div>
            <nav class="nav">
                <a href="#">服装城</a>
                <a href="#">美妆馆</a>
                <a href="#">尚品汇超市</a>
                <a href="#">全球购</a>
                <a href="#">闪购</a>
                <a href="#">团购</a>
                <a href="#">有趣</a>
                <a href="#">秒杀</a>
            </nav>
        </div>
    </div>
</template>

<script>
    import {mapState} from "vuex"
    import throttle from "lodash/throttle.js"
    export default {
        name: "TypeNav",
        data(){
          return {
              //当前展开的一级分类的下标
              // -2 : 处于一级分类的外部
              // -1 : 处于一级分类上
              // 其他大于0的值 : 选中一个一级分类了
              currentIndex:-2,
              //控制一级列表的显示&隐藏  当命中["/","/Home"]中的路由是 应该要显示一级列表 当前值为true
              showSort: ["/","/Home"].includes(this.$route.path)
          }
        },
        computed:{
            ...mapState({
                categoryList: state => state.home.categoryList,
                // searchVal : state => state.searchVal
            }),
            ...mapState(["searchVal"])
        },
        methods:{
            //代表移除一级分类区域
            itemWrapLeave(){
                this.currentIndex =-2;
                //除了home组件 其他都要隐藏一节分类
                if(!["/","/Home"].includes(this.$route.path)){
                    this.showSort = false
                }
            },
            //代表进入一级分类区域
            itemWrapEnter(){
                //新增一个代表进入一级分类区域的标志位 为了解决快速移除的bug
                this.currentIndex =-1;
                //显示一节分类
                this.showSort = true
            },
            //让当前index对应的一级分类的二三级分类显示出来
            itemEnter:throttle(function (index){
                //只有鼠标在一级分类上的时候 才允许它改变
                if(this.currentIndex !== -2){
                    this.currentIndex = index
                }
            },200),

            //三级分类跳转到search组件
            // toSearch({categoryName,category1Id,category2Id,category3Id}){
            toSearch(event){
                let localtion = {name:"Search"}
                //如果之前点击过搜索按钮 会携带上params数据
                let {keyword} = this.$route.params;
                //编程式路由进行跳转 这样可以避免创建过多的router-link组件
                const {categoryname,category1id,category2id,category3id} = event.target.dataset
                let query = {categoryName:categoryname};
                category1id ? query.category1Id=category1id : ""
                category2id ? query.category2Id=category2id : ""
                category3id ? query.category3Id=category3id : ""


                //如果header组件中的搜索输入框已经被人为的清空 那我们就不应该带上keyword
                if(this.searchVal==="")  keyword ="";
                keyword ? localtion.params = {keyword} : "";
                query ? localtion.query = query : "";
                // this.$router.push(localtion)

                //如果不是serach   跳 serach组件应该使用push
                //如果是serach 跳 serach组件应该使用replace
                if(this.$route.path.toLowerCase().startsWith("/search")){
                    this.$router.replace(localtion)
                }else{
                    this.$router.push(localtion)
                }

                //隐藏三级列表
                this.itemWrapLeave()
            }
        }
    }
</script>

<style scoped lang="less">
    .type-nav {
        border-bottom: 2px solid #e1251b;

        .container {
            width: 1200px;
            margin: 0 auto;
            display: flex;
            position: relative;

            .all {
                width: 210px;
                height: 45px;
                background-color: #e1251b;
                line-height: 45px;
                text-align: center;
                color: #fff;
                font-size: 14px;
                font-weight: bold;
            }

            .nav {
                a {
                    height: 45px;
                    margin: 0 22px;
                    line-height: 45px;
                    font-size: 16px;
                    color: #333;
                }
            }

            .sort {
                position: absolute;
                left: 0;
                top: 45px;
                width: 210px;
                height: 461px;
                position: absolute;
                background: #fafafa;
                z-index: 999;

                .all-sort-list2 {
                    .item {
                        h3 {
                            line-height: 30px;
                            font-size: 14px;
                            font-weight: 400;
                            overflow: hidden;
                            padding: 0 20px;
                            margin: 0;

                            a {
                                color: #333;
                            }
                        }

                        .item-list {
                            display: none;
                            position: absolute;
                            width: 734px;
                            min-height: 460px;
                            background: #f7f7f7;
                            left: 210px;
                            border: 1px solid #ddd;
                            top: 0;
                            z-index: 9999 !important;

                            .subitem {
                                float: left;
                                width: 650px;
                                padding: 0 4px 0 8px;

                                dl {
                                    border-top: 1px solid #eee;
                                    padding: 6px 0;
                                    overflow: hidden;
                                    zoom: 1;

                                    &.fore {
                                        border-top: 0;
                                    }

                                    dt {
                                        float: left;
                                        width: 54px;
                                        line-height: 22px;
                                        text-align: right;
                                        padding: 3px 6px 0 0;
                                        font-weight: 700;
                                    }

                                    dd {
                                        float: left;
                                        width: 415px;
                                        padding: 3px 0 0;
                                        overflow: hidden;

                                        em {
                                            float: left;
                                            height: 14px;
                                            line-height: 14px;
                                            padding: 0 8px;
                                            margin-top: 5px;
                                            border-left: 1px solid #ccc;
                                        }
                                    }
                                }
                            }
                        }

                        &.itemHover{
                            background: #f5f5f5;
                            .item-list {
                                display: block;
                            }
                        }
                    }
                }
            }
        }
    }
</style>